Imperial Astropaths indicate that high warp storm activity is indicitive of Dark Eldar and Chaos confrontation. Both factions dark Gods seem equally alligned to slaughter each other. A scouring of Veridian Secundus by both armies is about to lead to open warfare. Chaos Marines are already in the vacinity while Webway fluctuations indicate some kind of Dark Eldar force building up.
Only one of the Gods will prevail - but whose will is greater?